Cam-movement explosive-engine.



N0. 809,333. f PATENTED JAN. 9, 1906.

P. K. STERN.'

CAM MOVEMENT EXPLOSIVE ENGINE.

APPLICATION FIIED JAN. 22. 1903.

.h A H1 V n lun/lullin' llulllllllllllll.Illl'lllllllllllllll WgTNEEEESLNVENTUR mmm AUNITED STATES PATENT OFFICE..

CANI-MOVEMENT EXPLOSlVE-ENGINE.

Specification of Letters Patent.

Patented Jan. 9, 1906.

Application iiled January 22. 1903. Serial No. 140,087.

T0 all r11/"wm it may con/cern:

Be it known that I, PHILIP K. STERN, a citizen of the United States,residing in the city of New York, in the county and State of New York,have invented certain new and useful Improvements in Cam-MovementExplosive-Engines, of which the following is a specification.

My invention in explosive-engines relates to .internal-combustion motorsof the rapid combustion or explosive type, and has particular referenceto a means for converting the reciprocating movement of thepower-impressed kinematic member into a rotatory movement of the drivenmember, and vice versa.

The objects of my invention are, first, to provide a more compact andsimple means in the conversion of motion for engines of this characterand those in Vogue previous to my invention of which I am at presentaware, and, second, to reduce the weight of motors of this character inproportion to the amount of horse-power capacitythat the same isdesignedto develop and at the same time effect such changes in the constructionwhich will condense the parts into a more compact form than thoseemploying the crank and connecting-rod principle in the conversion ofthe motion of the reciprocating element.

In carrying out my invention I have selected that type known as thetwo-cycle rear compression explosive engine, to apply my principles, thedifferent characteristic features being clearly illustrated in thefigure, the same being a vertical sectional view taken through thecenter of the engine, so that one-half of the same nearest the observeris removed.

The different parts are identified by different characters of reference;but the same parts are designated by similar characters.

A constitutes the framework of the engine, which I prefer to constructof cast-iron; B, the fly-wheel or rotatory member; C, the cylinder orreciprocating element, and D the piston. Itwill be observed that thepiston y D is fixed to the framework by means of a head E, which isturned up true with the body F of the piston and is shouldered into abored recess'G and secured rigidly in position by bolts H, while thecylinder C is adapted to vibrate to and fro, so that a plane within thecylinder indicated by the dotted line I during an inward stroke of thecylinder C will fall upon the end of the piston and upon an outwardstroke of the cylinder the head J of the cylinder will move to theposition of the dotted line K. In order to restrain the cylinder Cagainst rotation, I provide two guiderods L and L', bolted to the head Eand secured by a screw-thread to a ring M, which pass throughperforations m m in a trunked piston-head O, which is formed integralwith the cylinder C, in a manner so as to form a cross-head sliding uponthe guide-rods L L The ring M is in turn secured to the frameworkagainst rotation by a series of bolts M', one of which in the drawingsuffices to illustrate their arrangement, and is drawn up against ashoulder formed in the framework, as shown, upon tightening the bolts Land L. To support the fly-wheel B so that'it will revolve about thecylinder C Without undue friction between the adjacent surfaces of thehub I) of the ily-wheel and the outer perimeter of the cylinder, Iprovide the usual babbitted bearing N, secured to the framework in acustomary manner by recesses and bolts, as illustrated. i In order toconvert the motion of the vibrating cylinder C into a movement of rota-Y tion at the fly-wheel, I form a diagonally-cut groove P upon theperimeter of the cylinder C, so as to form a sort of track or channelaround the same obliquely to the axis thereof, as indicated by thedotted lines, and I prefer to form this groove at what is known inmechanics as the critical angle with the axis of reciprocation, which isthe diagonal of a square contained between the two extreme diametricallyopposite points of the maj or axis of the ellipse thus formed and theopposite sides of the cylinder. The major axis of the ellipse would thenform the hypotenuse of a right isosceles triangle with two sides of thesaid angle, having its base along a line on the periphery of thecylinder and parallel with the axis of the same and the other side ofthe said angle being a perpendicular dropped from the origin of theangle at a diametrically opposite point in the cylinder upon the saidbase. The ellipse being in a diagonal plane through la section of acylinder when opened out upon a plane surface would form a figure whatis known in geometery as a sinusoid. This groove in mechanics is knownas a cam-groove, and its importance when its function is considered inconnection with the iy-wheel B and the conical roller p as the kinematicinstrumentalities to effect a mutual conversion of motion of TOO thereciprocating element C and the rotating member B will be manifest, aswill be understood by the hereinafter description relative thereto.

Secured to the fly-wheel B is a radially-disposed wrist-pin p and theconical roller or follower p aforesaid, which is a truncated cone,revolubly mounted on said wrist-pin p, having the origin of its apex ata point within the axis of rotation of the cylinder C and verticallyover the axis of the said wrist-pin. The roller p is adapted to rollupon the edge n and be just clear of the edge n of the grooved track Pwhen the cylinder C is moved outward or into the position of the dottedline K, which would be the effect of an internal pressure of the workingfluid in the combustion-chamber, acting between the inner end wall orhead J and the piston D, when the roller p would be brought into contactwith the edge n of the track or groove P in a manner so as to translateits movement into one of rotation in the fly-wheel B, and by the timethe cylinder C has reached the outward limit of its working stroke, sothat the cylinder-head J shall have coincided with the dotted line K,the roller p will have been brought to the apex of the elliptical curvedtrack P, and, as shown in the drawing, the cylinder C is approximatelyat the terminus of its outward working stroke and will then be ondead-center, and due to the inertia of the fiy-wheel B by the movementimparted to the same by the outward stroke of the cylinder C the rollerp will be carried past the point of dead-center in theellipticallyformed track or groove P on the opposite side of thediameter of the cylinder C, and the same will be returned to itsoriginal position. Thus it will be seen that for a complete revolutionof the iiy-wheel B a complete reciprocation is given to the cylinder C.That space of the cylinder contained between the piston D and the innerwall of the cylinder-head J and the inner cylindrical surface of thecylinder between these positions constitutes at any instance thecombustionchamber. If a belt be wrapped around the periphery of thefly-wheel B and the latter be driven by a source of continuous motion,it would be noted that the cylinder C will have what is known inmechanics as a simple periodic movement, in which case, however, thecontacting edges n and n of the elliptical track or groove willalternate during each half-revolution with the diametrically oppositepoints of the roller p at the instant of reversal of the reciprocatingcylinder C-that is to say, a change in the direction of motion of thecylinder C during its reciprocation by a constant rotatory member willchange the algebraic sign of motion of the coacting surfaces between thewalls or edges n n of the elliptical cam-groove P and correspondingpoints of contact upon the perimeter of the revolving follower p', whichwould give rise to hammering opposite faces of the follower and edges nn of the groove P, resulting finally in the break-down and destructionof the kinematic translating instrumentalities or parts thus coacting.

In order to maintain a constant pressure on but one face n of thecam-groove P, the algebraio sign of the impressed power should bechanged during each half-revolution, and to this end I have provided ameans whereby during one half-revolution the cylinder C is moved outwardby a positive force due to the power fluid of the cylinder, and thereturn stroke of the same is actuated by a negative force with respectto the cylinder C or by the inertia of the rotating element or fly-wheelB, thus satisfying the conditions requisite for a continuity of contactbetween the same edges or surfaces of the follower p and wall n of thecam-groove P, and in order to carry out this principle I have adapted acombustion-motor operating under what is known as the two-cycleprinciple in the manner following: As the cylinder C is moving inward bythe inertia of the fly-wheel B, the latter being previously set intomotion, the aspirating-space Q, contained between the ring M andtruncated piston-head D, will have its capacity increased sufficientlyto allow the inhalation of the combustible mixture from a suitablesupply-tank or carbureter to pass by way of the intake-pipe g andintake-valve g to the inhalation-space Q, and upon an outward movementof the cylinder C the combustible mixture taken into theinhalation-space Q will be compressd between the truncated piston O,which is made tight by packing-rings, as shown, and the annularabutment-ring M is likewise made tight, seating the intake-valve q' andunseating the check-valve q, allowing the mixture under compression topass by way of the fuelsupply port or inlet-passage r andspring-retracted inlet-valve r to the combustion-chamber. The saidfuel-supply port or inlet-passage 1 passes through the water-jacket dand is illustrated in the drawings as broken away about midway of itslength, showing the continuous annular water-jacket d, which isinterrupted for a portion of its circumference by the fuel-supply portor inlet-passage r. Upon the return stroke of the cylinder C the mixturewill be compressed by the decrease in capacity of the cylinder C due tothe piston D, and the inlet-valve r will be iirmly seated, and upon thecompression of the mixture to an extent commensurate with the capacityof the clearance-space contained between the dotted line l andinlet-valve r the same will be ignited in the usual manner by means ofthe ignition-plug B and the usual concomitant mechanism, and the enginewill receive its -first working stroke. At about the extremity of theoutward working stroke IOO IIO

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of the cylinder C the exhaust-valve R will be reciprocated, openingduring a period occupied by the movement of the rotatory meniber B orfly-wheel and closed by a retractingspring, the said opening beingeffected by means of the cam R, tappet-bar, and roller R, and tappet S,so as to admit the products of combustion into the interior T of thepiston, and finally out of the lateral exhaustopening T.

` In order to prevent undue heating of the cylinder, I provide awater-jacket d, annularly formed, as aforesaid, and having ports S andhaving a sliding connection for a length coincident with the stroke ofthe cylinder with a stationary water port or duct t and awater-inlet-pipe connection t', made integral with the casting E, whichis adapted to convey the water for cooling the cylinder C through a ports or water-jacket d and thence to a diametrically oppositely situatedcorresponding outlet-duct, ports, and passage-ways and outlet connectiont". By this manner of cooling I am enabled` to cool both the piston andthe cylinder from a xed point at the rear of the motor. During therearward movement of the truncated pistonhead O the volume of aircontained within the space L i s permitted to escape through theopenings U and V, thereby relieving the dead stroke of the cylinder C ofundue work.

In order to provide for effective lubrication of the different wearingparts, I have provided lubricating channels or ducts, as shown.

Having fully described the nature of my invention, whereby those who areskilled in the art to which the saine appertains could construct andoperate the saine, I claim as new and desire to secure by LettersIa'tent of the United Statesl. In a reciprocating explosive engine,wherein the motion of thereciprocating element actuated by an energizedpower medium, is adapted to be translated into a rotary motion at itsfly-wheel, a kinematic connection between the fiy-wheel and thereciprocating element located within the hub of the fly-wheel,forconverting the motion of the reciprocating element into a relativelyconstant rotatory motion of the fiy-wheel and conversely fortransforming a constant rotatory motion of the fiy-wheel into a periodicreciprocating motion of the reciprocating element, together withsuitable valve mechanism for controlling the working fiuid for saidengine, actuated by said fiy-wheel, substantially as described.

2. In a reciprocating explosive engine, wherein the motion of thereciprocating element actuated by an energized power medium is adaptedto be translated into a rotary motion at its fiy-wheel, akinematicconnection between the fiy-wheel and the reciprocating elementlocated within the hub of the fly-wheel, for converting the motion ofthe reciprocating element into a relatively constant rotatory motion ofthe fly-wheel and conversely for transforming a constant rotatory motionof the iiy-'wheel into a periodic reciprocating motion of thereciprocating element, a circulating fluid between said reciprocatingelement and saidfly-wheel, and a valve for controlling the working fluidfor said engine, together with means coacting between said fiy-wheel andsaid valve for actuating the latter upon the rotation of the saidfly-wheel substantially as described.

3. In an explosive-engine having areciprocating power element actuatedby an energized power medium and a rotatory member therefor,a kinematicconnection between the reciprocating power element and tlie'rotatorymember located at a point radiating from the axis of rotation of therotatory member, for translating the motion of the reciprocating powerelement into a relatively constant rotatory motion of the rotatorymember and conversely for transforming a constant rotatory motion of therotatory memberinto a periodic reciprocating motion of the reciprocatingpower element, a circulating fluid between the said reciprocating powerelement and said rotatory member, and a reciprocating valve forcontrolling the working fluid for the said engine, together with meanscoacting between said rotatory member and said valve for actuating thelatter upon the rotation of the said rotatory member; substantially asdescribed.

4. In an explosive-engine having a reciprocating power element actuatedby an explosive mixture and a rotatory member therefor adapted torevolve about said reciprocating power element, a kinematic connectionbetween the reciprocating power element and the rotatory member locatedat a point radiating froin the axis of rotation of the rotatory member,for translating the motion of the reciprocating power element into arelatively constant rotatory motion of the rotatory member andconversely for transforming a constant rotatory motion of the rotatorymember into a periodic reciprocating motion of the reciprocating powerelement, a circulating fluid between said reciprocating power elementand said rotatory member, a

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reciprocating valve for controlling the working fluid for said engine,together with means coacting between said rotatory member and said valvefor actuating the latter upon the rotation of the said rotatory memberand means for igniting said explosive mixture.

5. In an explosive -engine comprising a combustion-chamber having areciprocating power element actuated by an explosive mixture confined insaid combustion-chamber and a rotatory member adapted to revolve aboutsaid reciprocating power element, a kinematic connection between thereciprocating power element and the rotatory mem- ISO ber located at apoint radiating from the axis olE rotation of the rotatory member andexterior to said cylinder, for translating the motion of thereciprocating power element into a relatively constant rotatory motionof the rotatory member and conversely for transforming a constantrotatory motion ol the rotatory member into a periodic motion of thereciprocating power element, a circulating Huid between saidreciprocating power element and said rotatory member, a reciprocatingvalve for controlling the working vfluid for said engine, together withmeans coacting between said rotatory member and lsaid valve foractuating the latter upon the rotation of the said rotatory member andmeans located within the cylinder for igniting said explosive mixture.

6. In an explosive-engine, comprising a combustion-chamber having'areciprocating power element actuated by an explosive mixture confined insaid combustion-chamber and a rotatory member adapted to revolve aboutsaid reciprocating power element, a kinematic connection between thereciprocating power element and the rotatory mem- `ber located in an arcradiating from the axis vol" rotation of the rotatory member andconcentric with the exterior of said cylinder, for translating themotion of the reciprocating power element into a relatively constantrotatory motion of the rotatory member and conversely for transforming aconstant rotatory motion of the rotatory member into a periodicreciprocating motion of the reciprocating power element, a circulatingiluid between said reciprocating power element and said rotatory member,a reciprocating valve for controlling the working fluid for said engine,together with means coacting between said rotatory member and said valvefor actuating the latter upon the rotation of the said rotatory memberand means located within the cylinder for igniting the explosivemixture.

7. In an explosive-engine comprising a combustion-chamber having areciprocating power element actuated by an explosive mixture con'linedwithin said chamber and arctatory member adapted to revolve about saidreciprocating power element, said reciprocating power element adapted tovibrate along an axial line coincident with the axis of rotation of therotatory member, a kinematic connection between the reciprocating powerelement and the rotatory member, for translating the motion ofthereciprocating power element into a relatively constant rotatory motionof the rotatory member and conversely `for transforming a constantrotatory motion PHILIP K. STERN.

Witnesses I-I. M. MAHER, WILLIAM PAx'roN.

